Spindle for false twisting yarn

ABSTRACT

A spindle for false-twisting yarn comprising a rotatable body and yarn guides mounted in the body engaging said yarns. The guides are deflected under centrifugal action during rotation of the spindle to twist to yarn.

a United States Patent f mi lnventor Ernst August Weinz ldar-Oberstein, Germany Appl. No 872,049

Filed Oct. 29, 1969 Patented July 13, 1971 Assignee Ermt Fr. Weinz ldar-Oberstein, Germany Priority Oct. 31, 1968 Germany SPINDLE FOR FALSE TWISTING YARN 5 Claims, 6 Drawing Figs.

US. Cl .5 57/77.3 lnt.Cl D02g 1/06, DOlh 7/92 Field olSearch ..57/34,77.3-

.wf3,s91,953

[56] References Cited UNITED STATES PATENTS 2 430344 11/1947 Noguera.. 57/773 2,432,355 12/1947 Truin 57/773 X 2,515,299 7/195 0 Foster et al. 57/773 3,270,491 9/1966 Langen 57/773 X 3,292,357 12/1966 Richtor 57/77.45 3,349,554 10/1967 Boutonnet 57/77.3

Primary Examiner-Donald E. Watkins Attorney-Kurt Kelman ABSTRACT: A spindle for false-twisting yarn comprising a rotatable body and yarn guides mounted in the body engaging said yarns. The guides are deflected under centrifugal action during rotation of the spindle to twist to yarn.

PATENTEDJULIBIQTI 3.591.953

sum 1 0F 3 INVHN'I'ORI EM/JT A-WEWZ EVT PATENTEI] JUL 1 31971 SHEET 2 0F 3 v lNvliN'l'oR: ERUS'T, A. WEIUZ Are-Mr PATENTEDJULHIQH 3.591.953

SHEET 3 [IF 3 IN VENTORI ERA/$ A. WEI/V2.

WMM m SPINDLE FOR FALSE TWISTING YARN BACKGROUND OF THE INVENTION The present invention relates to apparatus for twisting yarn and, in particular, to a spindle for the false-twisting of yarn.

The false-twisting of yarn is a conventional method by which such characteristics as strength and elasticity are enhanced. The method is carried out by passing a heated yarn through a rotating spindle comprising a head provided with a longitudinal bore in which are situated a hook or eyelet device over which the yarn is engaged and twisted as it is drawn through the spindle. In practice the hooks or eyelets of the conventional devices created a great deal of friction, causing the yarn to weaken and develop capillary breaks along its surface. This factor is particularly troublesome during extremely high-speed operation.

A further defect resides in that the hooks and eyelets frequently allow the yarn to slip without twisting. As a result, the yarn speed and tension of the yarn create portions which are untwisted or which are too tightly twisted. This seriously affects the resultant uniformity, feel and appearance of the yarn.

Other disadvantages occur from the nonuniformity and nonregulatory nature of the prior art devices which must be operated at limited speed and with considerable care and attention.

It is a purpose of the present invention to provide an improved spindle which overcomes the disadvantages found in the prior art devices and, in particular, avoids capillary breakage of the yarn and slippage during the twisting operatron.

It is another object of this invention to provide a spindle which precisely and accurately imparts a false twist to a yarn.

It is yet another object of the invention to provide an improved spindle which regulates itself to the speed of operation so as to provide a uniform twisting operation during all stages.

It is a further object of the present invention to provide a spindle which is self-compensatory for fluctuation in wear, function and speed of operation.

It is a specific object of the invention to provide a spindle which does not use hooks or eyelets for engaging the yarn and so does not damage the yarn during the twisting operation.

Still more specific objects and advantages of this invention will be found in the following disclosure.

SUMMARY OF THE PRESENT INVENTION In accordance with the present invention, an improved spindle is provided having a central hollow section in which one or more freely rotatable elements are provided through which the yarn is passed. As the spindle is rotated, the freely rotatable elements are correspondingly caused to rotate by centrifugal action to cause the yarn to be deflected or twisted.

In one embodiment, the spindle is provided with a pair of guide members each of which is mounted on a shuttlelike element which freely moves in opposed radial direction as a result of the centrifugal rotation to pull the yarn simultaneously in opposite rotary directions to impart a twist thereto.

In a second embodiment, the guide members are mounted on the opposite peripheral ends of a ring pivoted in a direction perpendicular to the direction of yarn movement through the spindle. Under centrifugal action of the rotating spindle, the ring is pivoted so as to move the guide members in opposite rotary direction, correspondingly deflecting the yarn and imparting a twist thereto.

In a third embodiment, the guide members are supported on cantilevered leaf springs which are also movable by centrifugal action in opposite directions to correspondingly provide the twist to the yarn.

The guide members are preferably formed with a curved contour similar to an hourglass shape or configuration.

DESCRIPTION OF THE DRAWINGS In the drawing,

FIG. 1 is a sectional view ofa spindle embodying the principles of the present invention, taken along a plane running through its central longitudinal axis;

FIG. 2 is a sectional view of the spindle taken along line A-A of FIG. 1;

FIG. 3 is a sectional view in a plane running through the central axis of a second embodiment of a spindle embodying the principles of the present invention;

FIG. 4 is a sectional view similar to FIG. 3, with the spindle rotated about its longitudinal axis;

FIG. 5 is a sectional vicwin a plane running through the central axis ofa third embodiment; and

FIG. 6 is a sectional view similar to FIG. 5, with the spindle rotated 90 about its longitudinal axis.

Turning to the embodiment shown in FIGS. 1 and 2, the spindle is formed as a generally cylindrical assembly having a central section I and a top and bottom end cap 2 and 2', respectively. The central section land the end caps 2 and 2 are provided with radially interlocking cam faces, provided with low frictionless material, such as Teflon, which permits the same to be freely rotatable with respect to each other along a central longitudinal axis X-X.

The central section 1 and the bottom cap 2 are each provided with conically shaped bores 3 and 4, respectively. Each bore 3 and 4 flares upward toward the top cap 2, and the bores are aligned in the same general direction. The bores are drilled symmetrically about axes parallel to, but offset from, the central axis X-X, as well as from each other. This particular arrangement may be made by congruently milling the bores 3 and 4 but offsetting the radial cam faces so that the axes are offset eccentrically.

Both the top cap 2 and bottom cap 2 are provided with pins 5 and 5', respectively, which extend outwardly in opposed directions, to be held in and by suitable drive means so that the spindle may be rotated in a conventional manner. Each of the axle pins 5 and 5' has a central hole 6 and 6' lying along the axis of rotation X-X. The inner portions of the holes 6 and 6' extend within the spindle body itself and flare outwardly to communicate with the conically shaped bores 3 and 4, respectively. The bore 6 serves as the entrance for the yarn while the bore 6 serves as the exit for the yarn.

Located within the conical bores 3 and 4 are shaped shuttle members 7 and 7, respectively, each having an outer configuration or conical shape corresponding to the conical bore in which it is located. The shuttle members 7 and 7', however, are substantially smaller in size than either bore 3 or 4 so that the shuttle can be freely deflected within the bore, as indicated by the arrows 8 and 9. This deflection is centrifugal in nature since both bores and shuttle members are circular with respect to the axis of rotation X-X.

Each of the shuttle members 7 and 7 is provided with a smoothly turned central thread guide hole 10 and 10, respectively shaped in hourglass form so as to have a flared outer edge and a constricted central portion. The shuttle member 7 and 7 are sized so that the central holes 10 and 10' will straddle the central axis XX during rotation although their own central axes will be offset or eccentric to the axis X-X. The mount of eccentricity or offset of the axes of the shuttle members 7 and 7 will be easily predetermined so that the desired amount of deflection and consequent twist to the yarn is obtained.

The spindle is adapted to be mounted to receive yarn through the entrance bore 6 in the top cap 2 and pass the same through the holes 10 and 10' outwardly of the exit bore 6' in bottom cap 2. Conventional yarn pulling or winding means are employed to pass the yarn through the spindle. Such means will include bobbin windup means, and heat means suitable to preheat the yarn prior to or at the time of twisting, as is well known in this art. The axles 5 and 5' are mounted in conventional rotating means, such as a motor drive or bearing, so that either or both the pins are rotated, causing the spindle to turn about the axis )(-X. As the spindle rotates, the centrifugal force imparted thereto causes the shuttles 7 and 7 to ride against the inner periphery of the bores 3 and 4, thus causing the passing thread to be simultaneously deflected in two directions (8,9) and twisted as desired.

The yarn-engaging surfaces of the device, such as the holes and 10 are made of extremely smooth, hard and frictionless material, such as semiprecious stones like sapphire ruby, etc. or such materials as titanium diboride, ceramic oxide, cemented carbide, alumina or sintered borocarbide. These materials are preferred, although not essential since, as will be observed from the construction shown in FIGS. 1 and 2, the yarn is not passed over a hook or eyelet and is not acutely bent into a severe angular shape but is merely deflected from its course along the axis X-X by a smooth flared thread guide member 10 or 10.

The advantages of the present invention are obtained from the free mounting of the shuttle member within the bore 3 and 4 so that a free centrifugal movement is imparted to them. Thus, the force of deflection on the yarn is always in proportion to the speed at which the spindle is driven about the axis X-X and the speed at which the yarn may be pulled or passed through the device. Because of the symmetry of the device, it operates on the yarn under conditions of relative equilibrium and is self regulatory as to any fluctuations in friction or wear of the parts. Consequently, no matter at what speed the spindle may be rotated, the predetermined deflection of yarn and the frictionless passage of the yarn through the device is assured.

These same advantages may be obtained by maintaining the principles of the present invention in differing embodiments. For example, in the embodiment shown in FIGS. 3 and 4, the spindle is formed of a single unitary cylindrical member Ill having a hollow interior I2. The hinge or mounting axles 5 and 5 having a central bore 45 and 6, respectively, are also provided similar to the embodiment of FIGS. I and 2.

Mounted within the hollow interior I2 is a ring I35 which is provided with a pair of diametrically opposed pins 114 pivotally secured within the wall of the spindle illi. The ring 13 is arranged centrally within the interior I2 and the pins are located with their axes along a line 17, normal to the axis )(-X of the spindle so that the central axis of the ring may be caused to pivot about the vertical axis I7 within a plane common with the axis XX. The pins Ml may be provided with tension springs (not shown) normally biasing the ring 113 at an angle to the central axis X-)(.

,At the periphery of ring I3, an opposed diametrical face positions normal to the pivot pins 14, are a pair of arms I5 each holding a thread guide Mi. Each thread guide is shaped in hourglass fashion similar to the interior surface of the guide 10 or I0 shown in FIGS. l and 2. The thread guides 16 are preferably mounted as a roller rotatable about a central axis and are formed of the same hard semiprecious material as mentioned with respect to the guide holes I0 and I0.

The spindle shown in FIGS. 3 and 4 operates similarly to the spindle shown in FIGS. I and 2 by introducing the thread or yarn through the top bore 6 over the guide 16 through the ring 13 and outwardly of the bore t5. During movement of the yarn and rotation of the spindle, the ring 113 is pivoted about its axis 14 in the directions of the arrows shown in FIG. 4. The rotation of the spindle causes the ring 13 to move centrifugally about the pivot pins lli, tending to pivot the ring in a position in which its plane becomes normal to the axis XX. The bias on the axles 14 created by the strength of the springs employed as well as the movement of the yarn along the opposed guides surfaces l6 creates a torque on the thread which causes it to twist. The amount of torque on the thread is a function of the spindle speed (r.p.m.) as well as the spring bias.

In FIGS. 5 and 6 still another embodiment of the present invention is shown. In this embodiment, the outward configuration of the spindle is similar to that shown in FIGS. 3 and 4.

The interior I2 of the spindle body II is, however, provided with a pair of leaf springs 19 cantilevered outwardly from diagonally opposite corner edges 20. The leaf springs I9 respectively extend in substantially parallel planes to either side of the diagonal between the comers 2i) and 20 and over the center of the spindle so that their ends overly each other. The ends of the spring 19 are provided with rotatable thread guides 116 similar to those shown in FIGS. 3 and a. Each of the thread guides 16 is mounted along an axis transverse to the leaf spring 119 so that they lie in a plane parallel to the planes of the leaf spring and angular to the axis of rotation.

In this embodiment, the rotation of the spindle causes the leaf springs to move centrifugally outward of the center, deflecting in the directions of arrows 2ll, as seen in FIG. 6, causing a corresponding twist in the yarn fed through the device. As in the device shown in FIGS. 3 and 4, the strength of the leaf springs I9, the rotational speed of the spindle and the speed at which the yarn is pulled throughthe device, all af fect the degree of tension on the yarn and consequently the degree of twisting of the yarn.

In all embodiments, the thread guides are responsive to centrifugal action and vary their degree of torque on the yarn in proportion to that action. Consequently, friction is reduced to the minimum necessary to produce the twist, and breakage is avoided. High-speed operation is possible since the device is self-regulating and adjusts to variations in speed so as to provide a uniform twist. Yarn slippage is also avoided since the torque on the yarn producing the twist will remain uniform no matter at what speed the spindle is operated.

It will also be observed that the device is simply constructed and easily employed to provide economical operation at low initial cost and low labor input.

Since a number of embodiments have been shown and various modifications will become obvious to those skilled in the present art, the present disclosure is to be taken as illustrative only and not as limiting of the invention.

What I claim is:

l. A spindle for false-twisting yarns, comprising a rotatable body having an entrance and exit opening for the yarn and a hollow interior lying substantially along the axis of rotation, at least two yarn guides located within said interior substantially in alignment with the axis of rotation and engaging said yarn, said yarn guides being mounted so as to be freely movable radially with respect to said axis of rotation under centrifugal action to deflect said yarn and to twist said yarn as said spindle is rotated.

2. The spindle according to claim I, wherein each of said yarn guides comprises an hourglass shape having smooth curved surfaces provided with flared ends and a narrow cen tral portion.

3. The spindle according to claim I, wherein the yarn guides comprise a pair of shuttle members, said shuttle members being mounted within the body interior so that their bores lie in parallel but offset axes eccentric to the axis of rotation, said bores communicating with each other and the entrance and exit openings, each of said shuttles being substantially smaller in diameter than the body interior whereby, under centrifugal action, said shuttles are eccentrically rotated.

d. The spindle according to claim ll, wherein the yarn guides are mounted on opposite sides of a ring member, said ring member being mounted within the body interior so as to pivot about an axis normal to the axis of rotation of said spindle whereby, on rotation of said spindle, said ring member is pivoted, deflecting said yarn guide out of alignment with the axis of rotation and thereby twisting said yarn.

5. The spindle according to claim 11, including a pair of leaf springs each mounted at one end at diagonally opposed corners of the body interior, the yarn guides being respectively mounted on the free ends of said leaf springs, said leaf springs being of sufficient length to overly each other about the center of said body, said yarn guides being radially deflected on rotation of said spindles so as to deflect said yarn from the axis of rotation and impart a twist thereto. 

1. A spindle for false-twisting yarns, comprising a rotatable body having an entrance and exit opening for the yarn and a hollow interior lying substantially along the axis of rotation, at least two yarn guides located within said interior substantially in alignment with the axis of rotation and engaging said yarn, said yarn guides being mounted so as to be freely movable radially with respect to said axis of rotation under centrifugal action to deflect said yarn and to twist said yarn as said spindle is rotated.
 2. The spindle according to claim 1, wherein each of said yarn guides comprises an hourglass shape having smooth curved surfaces provided with flared ends and a narrow central portion.
 3. The spindle according to claim 1, wherein the yarn guides comprise a pair of shuttle members, said shuttle members being mounted within the body interior so that their bores lie in parallel but offset axes eccentric to the axis of rotation, said bores communicating with each other and the entrance and exit openings, each of said shuttles being substantially smaller in diameter than the body interior whereby, under centrifugal action, said shuttles are eccentrically rotated.
 4. The spindle according to claim 1, wherein the yarn guides are mounted on opposite sides of a ring member, said ring member being mounted within the body interior so as to pivot about an axis normal to the axis of rotation of said spindle whereby, on rotation of said spindle, said ring member is pivoted, deflecting said yarn guide out of alignment with the axis of rotation and thereby twisting said yarn.
 5. The spindle according to claim 1, including a pair of leaf springs each mounted at one end at diagonally opposed corners of the body interior, the yarn guides being respectively mounted on the free ends of said leaf springs, said leaf springs being of sufficient length to overly each other about the center of said body, said yarn guides being radially deflected on rotation of said spindles so as to deflect said yarn from the axis of rotation and impart a twist thereto. 